Forum 404 link error
 

New install vB 4.0.3
I posted an "internal" link to another post on my forum; the link was correct and was initially working fine.
After a forum member posted in the post where the initial link pointed the link does not work any more.

As a result of that, when clicking on my posted link everyone gets following error message: "The requested URL /forum/15-garmin-mapsource was not found on this server."

Any solutions for that?
Thanks